Robert Costa, the high-profile political reporter, is leaving his longtime home at The Washington Post to become a full-time television journalist at CBS News, where he will serve as the network’s chief election and campaign correspondent.

The move, to be announced on Thursday, is notable as much for Mr. Costa’s stature as a sought-after chronicler of national politics as it is for his decision to depart one of the more prominent roles in print journalism. Mr. Costa, 36, gained attention for his Congressional coverage at the right-leaning National Review magazine before joining The Post in 2014.

He is also the second well-known correspondent to exit The Post in recent days. David Fahrenthold, a 21-year veteran of the paper and a Pulitzer Prize winner for his investigations into the Trump family’s charitable donations, joined The New York Times earlier this month.

Mr. Costa, who co-wrote the book “Peril” with Bob Woodward last year, has plenty of experience in television news. He served as the moderator of “Washington Week” on PBS from 2017 to 2020, and was a regular presence on MSNBC and NBC News programs from 2015 to 2020, where he was a political analyst.

“I’ve worked across platforms for much of my career, and I believe it’s a vital time for me to grow as a storyteller, and to build my muscle as a reporter on the television front,” Mr. Costa said in an interview. “That excites me as a new challenge.”

Mr. Costa is a major hire by Neeraj Khemlani, the executive who took charge of CBS News last spring. Mr. Khemlani was an unexpected pick for the role who came to CBS from Hearst, a company best known as a magazine publisher. He has been focused on reimagining a storied news division — the former home of Edward R. Murrow — that has struggled in recent years to compete against ABC and NBC.

In the interview, Mr. Costa said he and Mr. Khemlani began discussing a possible role at the network in November. “It started as casual conversations about the future of American democracy and how important the coming years will be,” Mr. Costa said. He said the two men “built a bond.”

Mr. Costa said his arrangement with CBS will allow him to continue collaborating on some reporting projects with The Post.

“I am lucky to call Sally Buzbee and Fred Ryan friends,” Mr. Costa said, referring to the newspaper’s executive editor and publisher. “These are people I’ve worked closely with, and I appreciate their support for this decision.”

CBS News has filled several big roles this year. Mark X. Lima, formerly the network’s West Coast bureau chief, is now the Washington bureau chief. Anthony Galloway, the chief content officer at The Wall Street Journal, is joining CBS to oversee its streaming news programming.

There are no plans for Mr. Costa to host his own show. He is expected to appear on news programs across CBS’s broadcast and streaming platforms and play a major role in the network’s coverage of the 2022 midterms and 2024 presidential race.

Mr. Costa, who grew up in Pennsylvania, interned with the famed TV anchors George Stephanopoulos and Charlie Rose early in his career. He made a name for himself on the national stage with a string of scoops about the 2013 Republican-led shutdown of the federal government, earning a profile in New York magazine that declared him “the golden boy of the government shutdown.”